Method of forming electroplated articles and apparatus therefor



June 1 1926.

B. BART METHOD OF FORMING ELECTROPLATED ARTICLES AND APPARATUS THEREFOR Filed June 6, 1925 INVENTOR ATTORNEY Pat nted June 1, 1926.

' BLLBIUB m'r, OF EAST ORANGE, NEW JERSEY;

FHHTHOID OF FORMING- ELECTBOPLATED ARTICLES AND APPARATUS THEE E303.

Application am June a, 1925. sum in. 35,214. v

' provide for economy in current consumption; to increase the efficiency of operation by causing the electric energy consumed to do its maximum amount of useful work in depositing the metal where desired, and at 'the same time to minimize the destructive effect on the current conducting parts of the a paratus of the metal deposit forming w ere not needed or desired. b

It has been appreciated heretofore that all conducting surfaces connected with the opject being coated and immersed in the electrolyte solution, will receive a a deposit of metal and that the accumulating deposit necessitates increasing the current consumption in order to complete the desired deposition action on the mold or other object under treatment. Attempts have been made to remedy this condition in several ways, such for instance, as by supporting the work to "be treated on small readily re laceable hooks which could be removed w on they became coated. It has alsobeen proposed to sleeve the main current conducting rod with rubber hose or similar insulation inorder to economize in current loss .at least along the main arteries of current passage. The present invention distinguishes from the prior art basicly in that sim lified means are provided for insulating a1 conducting parts within the bath except where actual contact must be made with the mold or other surface to be coated, and in minimizing the area of such exposed parts to the least possible area that will maintain the requisite electric connection.

Another object of the invention is to provide a simple form of cathode plating hook which can be formed of separable sections so as to support anydesirednumberof molds or articles to be coated, and at the same time maintain the insulating properties featured in this disclosure. In the form of the inventlon herein select 'vide an article of manufacture which will ined for detailed discussion there is disclosed apparatus for formin an article inculding a preformedelement erein shown to be a brass ferrule and whichis welded electrolytically to the metal shell forming the remaming portion of the article; In-the present instance the replaceable ferrule constitutes part of the means for en plyin' the electric current to the prepare mol surface to be coated. Under such circumstances there is-a tendency for the depositing metal toaccumulate in a rough head at the line of jointure between the ferrule and the formed surface, due to the concentration of electr1c energy at this point exposed to the electrolyte.

. Another object of the invention therefore- 18 to provide an electrolytic weld between a preformed metal member and the shell or layer of metal being formed electrolytically and to insure such a form of welded jointure as will not be materially thicker than other portions of the deposited metal layer and which willfeature structural strength along the line of jointure, I

Broadly-this phase of the invention is attained by restraining the rate of flow of the electrolyte to the line of jointu-re. In the instant case the insulation herein featured is continued about the ferrule almost up to the line of jointure of the same with the mold and the insulating elements are designed and constructed to provide a constricted passageway for the electrolyte in its movement towards the line of jointure.

Another object of the invention is to proclude a Preformed metallic member, electrolytica ly welded to a shell formed electrolytically, and in which the line of jointure between the preformed and electrolytically formed arts will be neat in ap- Bgarance and WhlCh will avoid the heavy ad and irregular accumulation of deposits usually cles.

Various other objects and advantages of the invention will be in part obvious from a consideration of the method features of the disclosure and from an inspection of the accompanying drawings, and in part will be more fully set forth 1n the following parficular description of one method of practic formed at this point in such artiing the invention and in the inspection of a cathode hanger embodying certain mechanical features of my invention, and the invention also consists in certain new and novel modifications of the preferred method and other features of construction and combination of parts hereinafter set forth and claimed.

In the' drawings the figure is a View 1n vertical axial sect on of a plating hook illustrating a preferred embo iment of the mechanical aspects of the invention, illustrating an instrumentality by means of wh1ch the method herein featured may be practiced and showing in completed form a resultin article of manufacture.

In t e drawings the platin hook is shown to be formed of two separa 1e and similar ,to be a parts but it is understood that the hook when in use may be formed of one or any number of parts assembled in alinement to provide a hook of the desired length and to accommodate the desired number of molds or other articles to be coated.

There is shown a conducting rod comprising an upper section 10 and a' lower sec tion 11, the upper section being provided with a hooked end 12 for making connection with the bus bars or other source of electric energv usual in electrolytic tank constructions. At the lower end of eaol 1-'- rod is a metallic con-ducting couplingmember'13 in .screw threaded engagement therewith similarly threaded to the upper end of the next adjacent lower rod section. It is apreciated that these couplin means may orm a permanent part of eit er the upper or lower end of their associated rods and provide means for connecting the rods both mechanically and electricall As each rod section is simi ar to each other section, the detailed description of any one will be sufiicient for all.

The coupling 13 is provided at its lower end with an integral outstanding flange 14 the upper peripheral shoulder of which rovides a support for a metal ferrule 15 w ich encircles the coupling and extends above the same for a short distance as noted particularl in the upper portion ofthe fi ure.

or a (pur ose hereinafter descri ed the upper en 0 the ferrule is provided with an undercut peripheral groove 16 to constitute a mechanical lock for engaging with the electrolytic de osit as hereinafter described but it is un erstood that this groove is no material or necessary part of the present disclosure.

The upper end-of the ferrule provides a support for a mold 17 in this case shown lass mold including a curved underside 1 and having an outstanding flange 19. This particular form of mold-is designed to form flange arabolic .reflei itors of a well known type. t is understood that threaded on the conducting rod an .eral ro the surface of the mold which is to receive the electrolytic deposit has been previously coated with a conducting material such as graphite or the silver layer shown at 20 in t e lower part of the figure all as is well known in this art.

It will be understood from this construction that the ferrule 15 is in electric contact with the conducting rod at its lower and at its upper end in electric contact with the silver coating on the underside of the mold.

It is a feature of this disclosure to restrain, the usual rapid deposit of metal at the line of jointure 21 between the ferrule and the coating 20. For this purpose and also to prevent electric leakage from the conducting rod and coupling an open top insulating collar 22 underlaps the flan e 14 and extends upwardly about the ferru e 15 almost to its top, and in the instant case approximatel to. the lower edge of the groove 16. n order to insure an available supply of electrolyte to the line of jointure and at the same time to minimize the exposing of the current conducting parts which are carrying the maximum, amount ofv electric energy, the upper endiof'the collar 22 is beveled downwardly land lfoutwardly as shown at 23 and at an angle of ap roximatel 45. This construction provi es an exposin of the line of jointure to the electrolyte ut minimizes the area of exposure. All other parts of the conducting members are insulated from the electrolyte.

Above the mold this insulation is provided by an insulating sleeve 24 preferabl formed as a thin celluloid. tube and shrun on the conductin .rod so as to have a friction tight fit; 'T e insulating sleeve member may be used as one element of a clamp for securing the mold in position and in this case a metal reinforcmg rin 25 is is enclosed by a boxing 26 continuous with the insulation forming the sleeve 24:. In order to provide the necessary cushioning engagementwith the glass mold a rubber washer 27 ispositioned between the clamp thus describediand the upper inner face of the glass mold 18.

The lowermost insulatin collar 22 differs from the collars used t ereabove in the assembly in'that its bottom wall 28 is closed thus formin an end knob- 29 which will defeat any ten ency to electric leakage through the opening in the bottom of the wall 28 necessary with the other collars in order to make connection with the rod section therebelow.

In operation and assuming that the sevsections are disassembled, the upper rod sections with hook end is inverted with the hook down and the screw threaded end exposed. The upper glass mold with its silver coating is positioned on the threaded mg layers to a light but positive bearing engagement with the silver coated mold.

The operation of assembling molds androd sections is continued until finally the closing cap or knob 29 with its contained ferrule is screwed into engagement with the last rod section and the parts are then ready to be hung in the electrolytic tank and subjected to the depositing action of such tanks.

The deposit in this instance shown to be a copper deposit 30 is permitted to form as usual on the silver coating and to form in the undercut groove to provide a lockin connection 31. Instead of the usual bea which would otherwise form opposite" this groove the layer of preci itated metal forms with a smooth outer sur ace as shown at 32 and rounds into the upper side of the ferrule without any a preciable increase in thickness invmateria at this point than is present at the other portions of the deposit- There is eventually formed a parabolic shaped reflector with an outlining flange at its perimeter and a preformed ferrule which may preferably be of brass, at its apex."

By practicing the method herein' fea tured it is possible to economize ing cu rrent consumption and to efficiently direct the current uniformly over the silver or other coating, and there is neither an excessive deposit at the point of electrical connection with the coating nor is there developed the electrical losses which heretofore has occurred at this point. There is also avoided the loss both in current consumption and iii materials due heretofore to the accumulation of metal deposit on parts which were not desired to be coated; and as electric contact is maintained at all times with the coating it is not necessary to provide a separate means for insuring electric contact with the preformed metal surface.

While I have shown and described, and have pointed out in the annexed claims, certain novel features of my invention, it will be understood thatvarious omissions, substitutions and changes in the form and details of the device illustrated and in its 0 eration may be made by those skilled in t e art without departing from the spirit of the invention.

Having thus described my invention, I claim 1. In the art of coating a surface of a mold with a layer of metal electrolytically deposited, the method which consists in placing an electric conductor in contact with the mold, exposing said mold and conductor to the electrolyte forming the bath,

1 4. In a device of the and stopping off the deposit on the conductor except at the localized area of contact between the mold and conductor.

2. In the art of electrolytically welding a preformed metallic object to a metal shell incidental to the formation of the shell on its mold, the method which consists in preparing the mold to receive a metallic deposit, placing the preformed object in contact w1th the prepared mold, exposing the prepared mold and object to the action of an electrolytic bath, and stopping off the deposit from all portions of the object ex cept alon the line of contact between the object an the pre ared surface of the mold.

3. In the art 0 forming anarticle having a ferrule, the method which consists in positioning the ferrule to abut the mold surface on which the article is to be formed, subjecting the mold surface and ferrule so assembled to the action of' an electrolytic bath, using'the ferrule as a conductor of the electric current and stopping off the deposit from forming on the ferrule except adjacent its line of contact withthe mold surface.

combination of a cathod ng'er. including a rod formed of a plural (if sections with the upper section provided with a hook, coupling means at. thelower end of each section, a ferrule supported on each coupling means and connected electrically with the conducting rod, a mold supported on each ferrule, means between adjacent coupling means for insulating the exposed portion of the conducting rod therebetween, and means for insulating the coupling means said insulating means permitting ex posure of the end of each ferrule supporting its associated mold and acting otherwise to defeat electric leakage from the conducting rod.

described, the

5. In a device of the class described, the

member thereby to minimize electric leakage from all parts of the member except where it supplies the mold surface.

7. In a device of the class described, the

combination of a cathode hanger, a flange secured thereto, a metal form ferrule supported on the flange and in electric contact therewith, and a mold supported on the ferrule.

8. In a device of the class described, the combination of a cathode hanger, a flange secured thereto, a metal ferrule supported on the flange and in electric contact therewith, a mold supported on the ferrule and insulating means enclosing the hanger above the mold.

:9. In a deviceof the class described,- the combination of a cathode han er, a. flange secured thereto, a metal ferru e supported on the flange and in electric contact therewith, insulating meansenclosing the hanger above the mold, and about the flange and lower part of the ferrule.

10. In a device of the class described, the combination of a cathode hanger provided with a flange, a ferrule having an undercut groove adjacent its upper edge supported on said flange, an insulating collar surrounding said flange and extending upwardly therefrom about said ferrule substantially to the level of said groove, and a .mold resting on said ferrule and supported thereby above the insulating collar.

11. A cathode hanger for use in an electrolytic' tank, comprising a conducting member, means for supporting thereon an article to have a metal deposited electrolytically on the surface thereeof, the portion of said member exposed to the electrolyte being of the least possible area necessary to provide the requisite electrical connection with the surface on which the deposit is formed. i

12. A cathode hanger for an electrolytic bath, comprising conducting means, provided with a support for positioning thereon an object intended to receive a deposit of metal on a surface thereof, means for insulating all of said hanger which is to extend into the electrolyte except at the line of connection between said surface and said conducting means thereby to defeat tenden- Siy to form any metallic deposit on the conucting means.

13. A cathode hanger including a plurality of separate rods provided with means for securing the same, one in alinement with the other, each rod provided with means for mounting a mold thereon and in electric engagement therewith, each rod provided with an insulating member to enclose the exposed. portions of the rod and each rod provided with insulating means for encircling the securing means.

14. A cathode hanger including a plurality of separate rods adapted to be disposed in vertical alinement, means for electrically and physically connecting adjacent ends of the rods, an end knob formed of insulating material for enclosing the lower end of the lfiottom rod to prevent electric leakage there rom.

15. A cathode hanger including a rod provided at its upper end with means for making electric contact with a source of electric supply, a mold support adjacent its lower end, an insulating sleeve positioned on said rod and adapted to bear on the mold carried by-the support.

16. A cathode hanger including a rod provided at its upper end with means for making electric contact with a source of electric supply, a mold support adjacent its lower end, an insulating s eeve positioned on said rod and adapted to bear on the mold carried by the support, and an open top insulating sleeve encircling the mold support.

17. A cathode hanger comprising a rod, a coupling flange threaded to the lower end of a rod, an insulating sleeve surrounding the coupling flange and providing a space be tween t e sleeve and the rod for receiving a ferrule or the like.

18. A cathode hanger provided with means for supporting a mold in an electrolytic tank and provided with insulating means for defeating tendency of electric leakage therefrom, except to the parts of the mold desired to be coated.

19. In a device of the class described, the combination of a conducting rod having a flange adapted to support a ferrule on the.

rod, an insulating collar surrounding the flange and adapted to extend upwardly almost to the top of the supported ferrule, the upper edge of said collar being beveled downwardly and outwardly.

20. In a device of the class described, the combination of a conducting rod having a flange adapted to support a ferrule on the rod, an insulating collar surrounding the flange and adapted to extend upwardly almost to the top of the supported ferrule, the upper edge of said collar being beveled downwar ly and outwardly at an angle of approximately 15.

21. In a cathode hanger, the combination of a conducting rod provided with means for supporting a ferrule encircling the same and .in electric engagement therewith, an insulating collar surrounding said means and means for insulating a part of the rod exteriorly of said collar. 1

22. In a device of the class described, the combination of a conducting rod, means for supporting a mold on said rod, and an insulating sleeve surrounding the rod and adapted to prevent electric leakage from the part of the rod above the mold.

23. In a device of the class described, the

surrounding the rod, and a sleeve of insulating material surrounding the rod and ring. 25. An article of manufacture including 'a preformed metal ferrule having a groove a reformed metal ferrule having a groove ad acent one end, a layerof electrolytically deposited metal extended into said groove to lock the layer to the ferrule with a smooth curve formed between the layer-and ferrule along their line of juncture.

27. An article of manufacture includin a metal ferrule,a layer of electrolytically fieposited metal forming an electrolytic weld with one end of the ferrule, and said deposited metal at the line of jointure with the errule being of substantially the same thickness as the other parts of the deposited layer.

28. A reflector including a parabolic shell havin a metal ferrule at its apex, said shell including a backing of electrolytically deposited metal electrolytically welded to one end of the ferrule, and curving smoothly from the shell into the ferrule at the line ofjointure.

Signed at Newark, in the county of Essex and State of New Jersey, this 27th day of May A. D. 1925.

BLASIUS BART. 

